Tips for Kegging Lower-Carbonation Beers

[3 Dawg Night]

Sorry if you came here looking for tips; so am I.

What are some best practices for carbonating and serving lower-carbonation beers (e.g., English ales)? For instance, I'd like to brew a bitter, and the Brewer's Friend carbonation calculator tells me that at 38F (my normal keezer temp), I'll need -1.5 (yes, negative) psi to get 1.3 vols CO2. Obviously, I can't apply a vacuum to my keg, and even if I could, I wouldn't get any beer out of the tap. Even if I use a FermWrap to keep it at 50F, I'll need to put 1.75 psi on it, which would pour really slowly.

I'd like to avoid changing my keezer temperature, because I want to serve my other three taps at lower temperature. Although, I'm not opposed to adding a FermWrap and another temperature controller.

So, how do you keg/serve lower-carbonation beers?

 

[sibelman]

Insulation will not stop, but only slow, the equalization of temperature in your keg. And the BrewersFriend calculator seems weak (i.e. wrong) at the low end of the scale. Its own disclaimer states: No warranty or guarantee of accuracy is provided on the information provided by this calculator.

To your question, I'd guess that ~5psi will produce marginally carbonated beer at 38°F, notwithstanding the charts and calculators.

 

[3 Dawg Night]

Insulation will not stop, but only slow, the equalization of temperature in your keg. And the BrewersFriend calculator seems weak (i.e. wrong) at the low end of the scale. Its own disclaimer states: No warranty or guarantee of accuracy is provided on the information provided by this calculator.

To your question, I'd guess that ~5psi will produce marginally carbonated beer at 38°F, notwithstanding the charts and calculators.

Thanks for the response, but I'm confused about your insulation statement. Are you referring to the FermWrap? It's not insulation; it's an electric heater that wraps around a carboy/keg.

Are there better calculators out there, or are they all equally bad at low temperatures?

 

[sibelman]

I was confused about fermwrap - sorry. If the charts and calculators speak the truth, then you may need to embrace the higher (more style authentic?) temperature. However, if it were me, I would try low PSI at my usual temp first.

Seems to me you won't get any perceptible carbonation at 0 PSI, and only slight carb at low pressure. You don't really want flat beer, right?

 

[3 Dawg Night]

I was confused about fermwrap - sorry. If the charts and calculators speak the truth, then you may need to embrace the higher (more style authentic?) temperature. However, if it were me, I would try low PSI at my usual temp first.

Seems to me you won't get any perceptible carbonation at 0 PSI, and only slight carb at low pressure. You don't really want flat beer, right?

I want "authentic" beer. I guess if I don't like the low carbonation, I can crank it up.

 

[sibelman]

Yep. And your fridge won't have to fight the heat that would be added by the fermwrap.

 

[Sammy86]

So, how do you keg/serve lower-carbonation beers?

My initial thought is to naturally carb the keg...After looking at the carbonation chart the lowest it goes at 38F is 1.52. You could naturally carb the beer and then use a little pressure to serve.

Or you could go big fly, buy yourself a beer engine, naturally carb and have truly authentic English ales

 

[Dland]

You can leave the temp the same in your fridge, just carbonate to desired PSI for carbonation value desired for the beer style and temp you want to serve it at.

 

[Beermeister32]

If it were me, I’d carbonate in keg with corn sugar. It has the advantage of getting as close as possible to what you are looking for short of having true cask conditioning. Make sure to flush with CO2 after transfer and I’d add some ascorbic acid to retain freshness.

The question as I see it is how much carbonation seems right for your style and drinking habits. I think I’d try running a small experiment with some bottled ales with some Brewers Best conditioning tablets (or corn sugar if you have a good scale). Run a couple bottles using one tablet, a couple more at two tablets, more at three, four and five tablets per bottle. Test drink the bottles. I can assist in this task.

I believe a 5 tablet bottle roughly would equal that amount in a 4.3 ounce charge in a keg. You could then scale back to the amount found in your bottles.

So if your favorite was 3 tablets per bottle, that would be (3/5)*(4.3oz) = 2.58 ounces corn sugar per keg. Your mileage may vary!

 

[3 Dawg Night]

I like the several recommendations for naturally carbonating in the keg, but how do I serve it? Let's say I naturally carbonate to 1 vol CO2. If I then leave it on 5psi for serving, it will eventually equalize at higher than 1 vol. Is the solution just to turn off the gas between pints?

 

[Beermeister32]

Figure out your best level. If 3 carbonating tablets, that would be 60% of a standard 10 psi carbonation level of a standard keg charge, or 6 PSI.

So set your regulator to 6 psi for that example.

 

[3 Dawg Night]

My initial thought is to naturally carb the keg...After looking at the carbonation chart the lowest it goes at 38F is 1.52. You could naturally carb the beer and then use a little pressure to serve.

What are we calling "a little pressure to serve"? I decided to just force carb at 5 psi/38F to see where that gets me. I think that's going to result in just under 2 vols CO2.

Or you could go big fly, buy yourself a beer engine, naturally carb and have truly authentic English ales

I'd love to do that! Someday, when I am able to build my standalone brewshed/bar (i.e., after the kids graduate), I want to put in a beer engine for cask ales.

 

[Sammy86]

What are we calling "a little pressure to serve"? I decided to just force carb at 5 psi/38F to see where that gets me. I think that's going to result in just under 2 vols CO2.

2-3 PSI just to get the beer out with as little extra carbonation as possible!

I'd love to do that! Someday, when I am able to build my standalone brewshed/bar (i.e., after the kids graduate), I want to put in a beer engine for cask ales.

I follow a guy on IG who has his up and running after a European vacation...it is pretty slick and I'm very jealous of his English Ales!

 

[Hans O. Lowe]

Looks to me like the primary problem is with the serving temp. English ales (specifically cask ales) are served at cellar temp, which I believe is between 50 and 60 degrees. So at 55 degrees 7 psi will get you 1.53 volumes. That's as low as my chart recommends and sites stouts and porters at that level.

Serving at low pressure is as easy as shortening your serving line. It speeds up the pour but doesn't foam up because of the lower pressure.

 

[3 Dawg Night]

Looks to me like the primary problem is with the serving temp. English ales (specifically cask ales) are served at cellar temp, which I believe is between 50 and 60 degrees. So at 55 degrees 7 psi will get you 1.53 volumes. That's as low as my chart recommends and sites stouts and porters at that level.

Serving at low pressure is as easy as shortening your serving line. It speeds up the pour but doesn't foam up because of the lower pressure.

I have it hooked up to 20" of 4mm EVABarrier. At 5psi, it's still a trickle.

 

[doug293cz]

One solution is to go with beer gas (CO2/N2 mix.) With 30% CO2/70% N2 beer gas, your gauge pressure to get 1.3 volumes @38°F is 30 psi. This gives you a CO2 partial pressure of 13.5 psia, which is equivalent to a pure CO2 gauge pressure of -1.2 psig. (-1.2 psi is what ajdelange's equation gives for 1.3 volumes at 38°F.)

Brew on

 

[Hans O. Lowe]

I have it hooked up to 20" of 4mm EVABarrier. At 5psi, it's still a trickle.

Wow, that surprises me that 20" isn't working better. Lack of experience on my part I guess.

One solution is to go with beer gas (CO2/N2 mix.) With 30% CO2/70% N2 beer gas, your gauge pressure to get 1.3 volumes @38°F is 30 psi. This gives you a CO2 partial pressure of 13.5 psia, which is equivalent to a pure CO2 gauge pressure of -1.2 psig. (-1.2 psi is what ajdelange's equation gives for 1.3 volumes at 38°F.)

That's a really good idea!

 

[The_Antikveik]

Well cask ales (in Britain) are usually conditioned overnight for serving, after being tapped to slowly release excess CO2. So the trick is not worry too much if the beer’s too lively, just condition it for serving. When it comes to serving, without a beer engine, it’s a good idea to exploit gravity. A strategically positioned keg, on its side, slightly raised at the tap end with gas post at 12 o’clock, above the beer line. Several days to go bright, or sooner with a floating dip tube, and you’re good to go. Just add an open gas post during the pour. A ‘cask breather’ or propane regulator increases shelf life. Or fill a smaller keg.

 

[Hans O. Lowe]

A ‘cask breather’ or propane regulator increases shelf life. Or fill a smaller keg.

I really like the idea of casking at home, but these are the problems I run into. I wouldn't drink the beer fast enough before it went flat having a shielding gas (for lack of a better term) but not under pressure. Then I mentally circle back to where 3 Dawg Night is and I'm figuring out how to keg.

 

[The_Antikveik]

I have a small stainless cask (pin) and I love using it, but it only gets used once or twice a year, when I know it’s going to be emptied within an evening or day or two at the most. Even with a breather and beer engine. I use a sankey key or kegmenter and recondition a little when needed. Sometimes I’ll transfer some beer to a mini keg (up to 4.5L) for ‘conditioning‘ if I want to serve some through the beer engine without using the breather. There are a number of viable possibilities. Quite a few casked ales are served under gravity in the UK.

 

[SanPancho]

Sorry if you came here looking for tips; so am I.

What are some best practices for carbonating and serving lower-carbonation beers (e.g., English ales)? For instance, I'd like to brew a bitter, and the Brewer's Friend carbonation calculator tells me that at 38F (my normal keezer temp), I'll need -1.5 (yes, negative) psi to get 1.3 vols CO2. Obviously, I can't apply a vacuum to my keg, and even if I could, I wouldn't get any beer out of the tap. Even if I use a FermWrap to keep it at 50F, I'll need to put 1.75 psi on it, which would pour really slowly.

I'd like to avoid changing my keezer temperature, because I want to serve my other three taps at lower temperature. Although, I'm not opposed to adding a FermWrap and another temperature controller.

So, how do you keg/serve lower-carbonation beers?

get the following-
heat source
insulation
spunding valve- with decent/reliable control.

heat your keg. then wrap it with insulation. that'll keep the heat in the keg and not leaking (so much) out into the fridge.

carb your keg. natural or artificial, doesnt really matter. (unless you think it does) i see you have 1.75psi as target, but that's finer control than i've ever seen on a regulator. i'd wager you're going to have to just shoot for 2 and call it good enough.

with an empty keg, adjust the spunding valve until it reliably sets the keg back to 2psi. this will most likely be the hardest part. i'd do it like 5 times to make sure it sets and stays. ( a pressure gauge reading to only 5psi would be great here)

once you're confident in your spunding valve, you're set to go. set your regulator for whatever you want for PUSHING your beer. 5-10psi is a good place.

after you've poured yourself a beer or two, pop off the gas and slap on the spund. once its down to 2psi then pop off the spund and you're all set for next time. keg has enough pressure to stay sealed, and headspace is back to where it should be for carbonation equation. assuming you dont leave it in "serving" mode for more than an hour or two, the carbonation level will be unaffected. the lower the pressure you use to push the beer, the higher your safety margin.

rinse, lather, repeat.

 

[Erik the Anglophile]

I brew mostly English ales, only English stuff goes in my kegerator, I have resorted to naturally carbing to 2 vols in the keg and keeping the fridge at 10-12C and just under 1bar pressure.
The carbonation question can be solved by getting those longer tap nozzles and pouring rather aggressively, and then having the tap barely open for the last bit, to get a little foam.
Keep in mind a fresh cask is not flat, not yellow pisswasser fizzy, but you can definitely feel the carbonation.